The biggest growth area in our projects is now undoubtedly second storey additions. With good economical vacant land limited in the Sydney area many people are now opting for a second storey addition in lieu of building a new home.

2nd storey additions are also called first floor additions, attic conversions, Cape Cod extensions or top floor additions. They are all the same thing but they can be standard construction with frames and trusses or can be complex pitched roofs with dormer windows.

Previously owners risked over capitalising but now in many cases a 2nd storey addition can greatly increase the value of the home and be a good investment as well as adding more space.

First floor additions are much less disruptive to home owners than standard additions as work is completed above the existing home rather than in the owners yard. We do NOT require owners to leave their home while construction takes place. Our workers will enter the house via a window to the 2nd storey, not through the front door. Only after internal linings will the staircase opening be opened up to the ground floor, minimising any disruption to the owners

Carlingford job

Before photo

First floor addition in Carlingford

Mosman job

Before photo

Mosman luxury renovation

There are a few items that require special attention for 2nd storey additions. They include:

Transfer of points load

Installation method of waterproof tarp

Construction program until house is waterproof

Neighbours privacy

Light weight construction materials

Removal of existing ground floor walls to open up living areas

2nd storey additions require good organisation and access to a large carpentry team to ensure the waterproof stage is reached quickly, minimising the chance of leaks. 2nd storey additions are therefore not usually suitable to owner builders or smaller on-site working builder companies.

For second storey additions to work well the builder needs very detailed planning, a dedicated hard working team of carpenters, attention to detail and above all patience. If the weather looks bad the project needs to be delayed at the appropriate time to minimise any leaks. OMara is very experienced at the process of second storey additions.

St Ives Before Photo

St Ives After Photo

St Ives Externally After Photo

St Ives Sunroom

After signing building contracts we will not commence work on-site for a couple of weeks until a large amount of materials have been delivered to site so that no delays occur waiting for materials. We usually start work on a Monday and the process will involve the following steps;

1. Delivery of materials2. Relocation of aerial power service (if required)3. Strip roof tiles / roof and dispose or store on site for reuse4. Cut back roof timbers5. Pack up wall frames and install floor joists6. Install internal drainage for first floor bathrooms7. Install new air-conditioning ducting as required

At this stage the house is now waterproof and the chance of any leaks to the ground floor is greatly reduced. Only very minor leaks should now occur. We usually reach this waterproof stage with 10 to 15 working days. If the project includes pitched rafters rather than trusses or metal roofing it may take longer to reach this stage. Extremely large additions can also take a bit longer but this time frame usually allows for a 2nd storey addition of around 12m x 8m, a typical size.

O'Mara constructions has completed a number of first floor additions using standard construction and alternate building materials. Photographs and references can be supplied upon request.

Please contact our office for details.

St Ives internal fireplace

St Ives Kitchen / Dining

Beverly Hills project (BEFORE PHOTO)

Beverly Hills Project nearing completion November 2012

In some instances "Posi-strut" open web floor joists are used which allows for services such as air-conditioning ducting. In other circumstances Hyspan or Hynebeam joists (which are laminated timber joists) are a better option. Sometimes it is better to raise the height of the area between the existing ceiling and the new floor joists. Each project requires careful consideration in the planning stage of which is the most suitable method.

Owners need to select bathroom fittings such as bath tubs, toilet suites and vanity units prior to construction commencement so that the appropriate allowances can be made at the floor joist framing stage. OMara has a special method of construction that is more flexible and allows for future changes but it is still critical that these selections are made at an early stage.

Our experience is that quiet often the existing ceiling space can be very dirty. It can contain old dusty insulation, spray-in type insulation, rat vermin, dead birds, birds nests and many other horrible things. We recommend that all owners considering completing a second storey addition that they employ the builder to clean-up the ceiling space. Upon request we can vacuum out completely the existing ceiling, remove all old duct ridden insulation, install new clean insulation and install downlight protectors (which is one of the biggest causes of house fires) prior to installation of the new sheet flooring, This is the only opportunity the owners will have to clean-up this area as it will then be sealed forever after installation of the new floor.

CONSTRUCTION COST

The exact cost of a second storey addition depends on the size of the addition and the amount of work required to the existing house. Some clients choose to remove ground floor internal walls to create more open space, cement render or paint the existing house, renovate bathrooms or kitchens and alike. However our most typical first floor addition consists of a new master bedroom, walk-in-robe, ensuite, two other new bedrooms and a small sitting room. Extensions of this size are usually around 12x8m in size. Typically these size extensions costs around $165,000 + GST for the first floor addition work. This equates to a square metre rate of $1,650/m2. Although square metre rates can very inaccurate in some cases it can give owners a rough idea of construction costs. The cost for the ground floor work would need to be added to this budget cost. This would include items such as rendering the ground floor brickwork, removing existing house internal walls, re-tiling the existing roof, renovating existing bathrooms or kitchens.

To confirm this budget price owners need to first have a "draft concept" plan prepared. This plan consists of a floor plan of the extension drawn to scale with a few basic dimensions, 1 or 2 elevations and a site plan. From this draft plan we can price the construction cost exactly, price alternatives in design and inclusions and obtain verbal council development approval. We can also submit a separate price to arrange all the professional designs required to obtain council development approval. We usually recommend that the owners obtain this "concept plan" directly. This way the owners retain full rights of the design of the addition. If the builder prepares the plans the he usually owns the rights to the plans and only he can build the job and the owner cannot check his price if fair and reasonable.